US7702223B2 - Circuit for controlling rotation speed of computer fan - Google Patents
Circuit for controlling rotation speed of computer fan Download PDFInfo
- Publication number
 - US7702223B2 US7702223B2 US12/036,273 US3627308A US7702223B2 US 7702223 B2 US7702223 B2 US 7702223B2 US 3627308 A US3627308 A US 3627308A US 7702223 B2 US7702223 B2 US 7702223B2
 - Authority
 - US
 - United States
 - Prior art keywords
 - pin
 - fan
 - controller
 - amplifier
 - circuit
 - Prior art date
 - Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
 - Expired - Fee Related, expires
 
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Classifications
- 
        
- G—PHYSICS
 - G06—COMPUTING OR CALCULATING; COUNTING
 - G06F—ELECTRIC DIGITAL DATA PROCESSING
 - G06F1/00—Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00
 - G06F1/16—Constructional details or arrangements
 - G06F1/20—Cooling means
 - G06F1/206—Cooling means comprising thermal management
 
 
Definitions
- the present invention relates to computer fans, and particularly to a circuit for controlling rotation speed of a computer fan.
 - a computer system includes a motherboard with various chips such as a central processing unit (CPU) mounted thereon, a storage device such as a hard disc, and input/output devices. Many of these devices generate heat when the computer system is operating, particularly the CPU. If the heat generated from the CPU is not dissipated in a timely fashion, it may damage the CPU or even the computer system.
 - CPU central processing unit
 - storage device such as a hard disc
 - a sensor is programmed to be used as a temperature detector for detecting the temperature of the CPU.
 - a computer fan is used to facilitate removal of heat to keep the temperature of the CPU within a safe temperature range.
 - a fan controller is provided to adjust the fan speed to be more energy efficient while still providing enough heat dissipation.
 - Two common kinds of computer fans are 3-pin fans and 4-pin fans.
 - the fan speed of a 3-pin fan can be adjusted by changing a voltage signal (power signal) input to the 3-pin fan.
 - the fan speed of a 4-pin fan can be adjusted by a pulse-width modulation (PWM) signal controlled by a basic input/output system (BIOS) of the motherboard directly to the 4-pin fan.
 - PWM pulse-width modulation
 - a 3-pin fan motherboard a 3-pin fan is connected to the motherboard by a 3-pin header mounted on the motherboard, and a 3-pin fan controller is provided to supply the voltage signal to the 3-pin fan for adjusting the rotation speed of the 3-pin fan.
 - a 4-pin fan motherboard a 4-pin fan is connected to the motherboard by a 4-pin fan header mounted on the motherboard, and a 4-pin fan controller is provided to supply the PWM signal to the fourth pin of the 4-pin fan for adjusting the rotation speed of the 4-pin fan.
 - the 3-pin fan can be connected to the 4-pin fan motherboard by the 4-pin header.
 - the 3-pin fan cannot be controlled by the 4-pin fan controller because the 3-pin fan does not have the fourth pin and cannot receive the PWM signal. Therefore, the CPU may be damaged because the heat may not be dissipated properly.
 - What is needed is a circuit for adjusting the rotation speed of a computer fan whether the computer fan is a 3-pin fan or a 4-pin fan.
 - An exemplary circuit for controlling rotation speed of a computer fan includes a fan header configured for connecting to a 4-pin fan or a 3-pin fan, a jumper device, an amplifier, and a controller.
 - the jumper device has a first pin configured for receiving a controlling signal, and connected to a first power source, a second pin connected to the fan header, and a third pin connected to the first power source.
 - the amplifier has an input terminal connected to the third pin of the jumper device via an integrator.
 - the controller has a first terminal connected to an output terminal of the amplifier, a second terminal connected to a second power source, and a third terminal connected to the fan header and connected to a positive input terminal of the amplifier via a resistor.
 - the first pin of the jumper device is selectively connected to the second or third pin.
 - FIG. 1 is a diagram of a circuit for controlling rotation speed of a computer fan in accordance with an exemplary embodiment of the present invention.
 - FIG. 2 is a diagram of another exemplary embodiment of the amplifier of FIG. 1 .
 - a circuit for controlling rotation speed of a computer fan in accordance with an exemplary embodiment of the present invention includes a jumper device 10 having three pins 11 , 12 , and 13 , a transistor T functioning as a controller, an amplifier U, a fan header having 4 pins 1 , 2 , 3 , and 4 , a plurality of resistors R 1 ⁇ R 7 , and two capacitors C 1 , C 2 .
 - the pin 11 of the jumper device 10 is connected to a 5V power source via the resistor R 1 , and is connectable to the pin 12 or 13 of the jumper device 10 by a jumper selectively.
 - the pin 12 of the jumper device 10 is grounded via the resistor R 2 and the capacitor C 1 , which form an integrator by being connected in series, and also being connected to the 5V power source via the resistor R 3 .
 - the pin 13 of the jumper device 10 is connected to the pin 4 of the fan header.
 - the pin 11 of the jumper device 10 is configured for receiving a PWM signal controlled by a super input/output (SIO) controller of the motherboard.
 - SIO super input/output
 - the amplifier U includes a negative input terminal which is connected to a node between the resistor R 2 and the capacitor C 1 , a positive input terminal which is grounded via the resistor R 6 , a power terminal connected to a 12V power source, and an output terminal.
 - the base of the transistor T is connected to the output terminal of the amplifier U via the resistor R 4 , the emitter of the transistor T is connected to the 12V power source, and connected to the base via the resistor R 7 , the collector of the transistor T is connected to the pin 2 of the fan header 20 , and connected to the positive input terminal of the amplifier U via the resistor R 5 , and is grounded via the capacitor C 2 .
 - the pin 1 of the fan header 20 is grounded, and the pin 3 is configured for connecting to the SIO controller to detect temperature of the CPU.
 - the pin 11 of the jumper device 10 is connected to the pin 12 via the jumper.
 - the SIO controller sends a PWM signal according to temperature of the CPU to the negative input terminal of the amplifier U via the integrator, which rectifies the PWM signal (digital voltage signal) to an analog voltage signal.
 - the amplifier U receives the analog voltage signal and outputs an amplified voltage signal.
 - the amplified voltage signal controls a quiescent operating point of the transistor T via the resistor R 4 , and the transistor T outputs a fan control signal based on the voltage signal to the pin 2 of the fan header 20 . Therefore, the 3-pin fan connected to the fan header 20 is adjusted by changing the quiescent operating point of the transistor T.
 - the pin 11 of the jumper device 10 is connected to the pin 13 via the jumper.
 - the 5V power source outputs an invariable voltage to the negative input terminal of the amplifier U via the resistors R 2 and R 3 , and the amplifier U outputs an invariable voltage to the base of the transistor T.
 - the 12V power source provides a working voltage for the 4-pin fan via the transistor T and the pin 2 of the fan header 20 .
 - the SIO controller sends a PWM signal to the fan header 20 , and changes the rotation speed of the 4-pin fan connected to the fan header 20 by adjusting the duty cycle of the PWM signal according to temperature of the CPU. Therefore, the 4-pin fan is adjusted by using PWM signals.
 - the amplifier U is replaced with a positive-negative-positive (PNP) transistor Q 1 and an negative-positive-negative (NPN) transistor Q 2
 - the transistor T is replaced with a P-channel metallic oxide semiconductor field effect transistor (P-channel MOSFET) Q 3 .
 - the base of the transistor Q 1 is connected to the node between the resistor R 2 and the capacitor C 1
 - the emitter of the transistor Q 1 is connected to the 12V power source via a resistor R 10
 - the collector of the transistor Q 1 is grounded.
 - the base of the transistor Q 2 is connected to the emitter of the transistor Q 1 , the collector of the transistor Q 2 is connected to the 12V power source via a resistor R 12 , and the emitter of the transistor Q 2 is grounded via the resistor R 6 .
 - the gate of the P-channel MOSFET Q 3 is connected to the collector of the transistor Q 2 , the source of the P-channel MOSFET Q 3 is connected to the 12V power source, and the drain of the P-channel MOSFET Q 3 is connected to the pin 2 of the fan header 20 and further connected to the emitter of the transistor Q 2 via the resistor R 5 .
 - a drain current of the transistor Q 3 is changed by changing the channel width of the transistor Q 3 , therefore, the rotation speed of the 3-pin fan is adjusted.
 - the 4-pin fan can be adjusted by using PWM signals.
 
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- Engineering & Computer Science (AREA)
 - Theoretical Computer Science (AREA)
 - Human Computer Interaction (AREA)
 - Physics & Mathematics (AREA)
 - General Engineering & Computer Science (AREA)
 - General Physics & Mathematics (AREA)
 - Cooling Or The Like Of Electrical Apparatus (AREA)
 - Control Of Electric Motors In General (AREA)
 
Abstract
Description
Claims (12)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title | 
|---|---|---|---|
| CN2008103000258A CN101477391B (en) | 2008-01-04 | 2008-01-04 | Control circuit for computer fan | 
| CN200810300025.8 | 2008-01-04 | ||
| CN200810300025 | 2008-01-04 | 
Publications (2)
| Publication Number | Publication Date | 
|---|---|
| US20090175602A1 US20090175602A1 (en) | 2009-07-09 | 
| US7702223B2 true US7702223B2 (en) | 2010-04-20 | 
Family
ID=40838117
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date | 
|---|---|---|---|
| US12/036,273 Expired - Fee Related US7702223B2 (en) | 2008-01-04 | 2008-02-24 | Circuit for controlling rotation speed of computer fan | 
Country Status (2)
| Country | Link | 
|---|---|
| US (1) | US7702223B2 (en) | 
| CN (1) | CN101477391B (en) | 
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title | 
|---|---|---|---|---|
| US20050222534A1 (en) * | 2004-03-30 | 2005-10-06 | Takefumi Uesugi | System and method for supplying predetermined gas at two different pressure values | 
| US20100033120A1 (en) * | 2008-08-06 | 2010-02-11 | Fei Wang | Fan speed control system | 
| US20100145548A1 (en) * | 2008-12-04 | 2010-06-10 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Fan driving circuit | 
| US20110175562A1 (en) * | 2010-01-20 | 2011-07-21 | Hong Fu Jin Precision Industry (Shenzhen)Co., Ltd. | Fan circuit | 
| US20110243713A1 (en) * | 2010-03-30 | 2011-10-06 | Hon Hai Precision Industry Co., Ltd. | Fan control circuit | 
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title | 
|---|---|---|---|---|
| CN101464694B (en) * | 2007-12-21 | 2012-06-20 | 鸿富锦精密工业(深圳)有限公司 | Control circuit for computer fan | 
| CN101477391B (en) * | 2008-01-04 | 2011-11-30 | 鸿富锦精密工业(深圳)有限公司 | Control circuit for computer fan | 
| CN101963150B (en) * | 2009-07-21 | 2014-08-13 | 鸿富锦精密工业(深圳)有限公司 | Fan type detection and speed regulation system | 
| TWI461694B (en) * | 2009-07-29 | 2014-11-21 | Hon Hai Prec Ind Co Ltd | System for detecting type and controlling rotary speed of fan | 
| CN102042249B (en) * | 2009-10-12 | 2014-12-03 | 国家电网公司 | Control circuit of computer fan | 
| TWI453418B (en) * | 2010-03-26 | 2014-09-21 | Hon Hai Prec Ind Co Ltd | Measuring system for rotating speed of fan | 
| CN102261343A (en) * | 2010-05-26 | 2011-11-30 | 中兴通讯股份有限公司 | Device and method for speed regulation of fan | 
| EP2503735B1 (en) * | 2011-04-13 | 2018-03-07 | Huawei Technologies Co., Ltd. | Multi-service node management system, device and method | 
| CN102955509B (en) * | 2011-08-31 | 2017-07-21 | 赛恩倍吉科技顾问(深圳)有限公司 | Hard disk backboard and hard disk storage system | 
| CN103807192A (en) * | 2012-11-06 | 2014-05-21 | 鸿富锦精密工业(武汉)有限公司 | Computer fan control circuit | 
| CN103867471B (en) * | 2012-12-11 | 2016-12-21 | 国网山东省电力公司东营供电公司 | Wind energy supply system and there is the electronic installation of this wind energy supply system | 
| CN104033409B (en) * | 2013-03-07 | 2016-09-14 | 鸿富锦精密电子(天津)有限公司 | Fan power supply circuits | 
| CN104235034A (en) * | 2013-06-17 | 2014-12-24 | 鸿富锦精密电子(天津)有限公司 | Fan circuit | 
| CN104728147B (en) * | 2013-12-24 | 2016-08-17 | 国家电网公司 | Fan control circuitry | 
| CN104750205A (en) * | 2013-12-30 | 2015-07-01 | 鸿富锦精密工业(武汉)有限公司 | Fan control circuit | 
| CN105739660A (en) * | 2014-12-10 | 2016-07-06 | 鸿富锦精密工业(武汉)有限公司 | Voltage regulation device of electronic equipment | 
| CN106054077A (en) * | 2016-07-08 | 2016-10-26 | 珠海格力电器股份有限公司 | Speed regulation voltage switching circuit and power panel | 
| CN111025303A (en) * | 2019-11-29 | 2020-04-17 | 清华大学苏州汽车研究院(吴江) | Vehicle-mounted embedded ultrasonic sensor system | 
| CN111736662A (en) * | 2020-05-28 | 2020-10-02 | 苏州浪潮智能科技有限公司 | A server fan protection control device | 
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title | 
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| US20050016191A1 (en) * | 2003-07-25 | 2005-01-27 | Butler William P. | Unitary control for air conditioner and/or heat pump | 
| US20070019383A1 (en) * | 2005-07-09 | 2007-01-25 | Chang Yu-Chen | System and method for automatically detecting a type of a cpu fan | 
| US20070108923A1 (en) * | 2005-11-16 | 2007-05-17 | Tyan Computer Corporation | Apparatus and method for driving different fans | 
| US20070148019A1 (en) * | 2005-12-28 | 2007-06-28 | Inventec Corporation | Method and device for connecting several types of fans | 
| US20070229291A1 (en) * | 2006-03-31 | 2007-10-04 | Tyan Computer Corporation | Universal apparatus for driving diverse fans | 
| US20070292257A1 (en) * | 2006-06-15 | 2007-12-20 | Ghee Beng Ooi | Apparatus and method to provide reduced fan noise at startup | 
| US20080004755A1 (en) * | 2006-06-28 | 2008-01-03 | Dunstan Robert A | Apparatus and method for automatically configuring control of a fan to be exclusively performed by a motherboard | 
| US20080095521A1 (en) * | 2006-10-18 | 2008-04-24 | Hon Hai Precision Industry Co., Ltd. | Control circuit for a fan | 
| US20090003806A1 (en) * | 2007-06-29 | 2009-01-01 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Method and circuit for controlling rotation speed of computer fan | 
| US20090162039A1 (en) * | 2007-12-21 | 2009-06-25 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Circuit for controlling rotation speed of computer fan | 
| US20090169188A1 (en) * | 2008-01-02 | 2009-07-02 | Winbond Electronics Corporation | Apparatus and method for fan auto-detection | 
| US20090175602A1 (en) * | 2008-01-04 | 2009-07-09 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd | Circuit for controlling rotation speed of computer fan | 
| US20090208192A1 (en) * | 2008-02-18 | 2009-08-20 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd . | Device for controlling rotation speed of computer fan | 
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title | 
|---|---|---|---|---|
| CN100395955C (en) * | 2005-07-29 | 2008-06-18 | 鸿富锦精密工业(深圳)有限公司 | DC fan start circuit | 
- 
        2008
        
- 2008-01-04 CN CN2008103000258A patent/CN101477391B/en not_active Expired - Fee Related
 - 2008-02-24 US US12/036,273 patent/US7702223B2/en not_active Expired - Fee Related
 
 
Patent Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title | 
|---|---|---|---|---|
| US20050016191A1 (en) * | 2003-07-25 | 2005-01-27 | Butler William P. | Unitary control for air conditioner and/or heat pump | 
| US7100382B2 (en) * | 2003-07-25 | 2006-09-05 | Emerson Electric Co. | Unitary control for air conditioner and/or heat pump | 
| US7464561B1 (en) * | 2003-07-25 | 2008-12-16 | Emerson Electric Co. | Unitary control for air conditioner and/or heat pump | 
| US7444824B1 (en) * | 2003-07-25 | 2008-11-04 | Emerson Electric Co. | Unitary control for air conditioner and/or heat pump | 
| US20070019383A1 (en) * | 2005-07-09 | 2007-01-25 | Chang Yu-Chen | System and method for automatically detecting a type of a cpu fan | 
| US20070108923A1 (en) * | 2005-11-16 | 2007-05-17 | Tyan Computer Corporation | Apparatus and method for driving different fans | 
| US7501717B2 (en) * | 2005-11-16 | 2009-03-10 | Tyan Computer Corporation | Apparatus and method for driving different fans | 
| US20070148019A1 (en) * | 2005-12-28 | 2007-06-28 | Inventec Corporation | Method and device for connecting several types of fans | 
| US7355359B2 (en) * | 2006-03-31 | 2008-04-08 | Tyan Computer Corporation | Universal apparatus for driving diverse fans | 
| US20070229291A1 (en) * | 2006-03-31 | 2007-10-04 | Tyan Computer Corporation | Universal apparatus for driving diverse fans | 
| US20070292257A1 (en) * | 2006-06-15 | 2007-12-20 | Ghee Beng Ooi | Apparatus and method to provide reduced fan noise at startup | 
| US20080004755A1 (en) * | 2006-06-28 | 2008-01-03 | Dunstan Robert A | Apparatus and method for automatically configuring control of a fan to be exclusively performed by a motherboard | 
| US20080095521A1 (en) * | 2006-10-18 | 2008-04-24 | Hon Hai Precision Industry Co., Ltd. | Control circuit for a fan | 
| US7541762B2 (en) * | 2006-10-18 | 2009-06-02 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Control circuit for a fan | 
| US20090003806A1 (en) * | 2007-06-29 | 2009-01-01 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Method and circuit for controlling rotation speed of computer fan | 
| US20090162039A1 (en) * | 2007-12-21 | 2009-06-25 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Circuit for controlling rotation speed of computer fan | 
| US20090169188A1 (en) * | 2008-01-02 | 2009-07-02 | Winbond Electronics Corporation | Apparatus and method for fan auto-detection | 
| US20090175602A1 (en) * | 2008-01-04 | 2009-07-09 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd | Circuit for controlling rotation speed of computer fan | 
| US20090208192A1 (en) * | 2008-02-18 | 2009-08-20 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd . | Device for controlling rotation speed of computer fan | 
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title | 
|---|---|---|---|---|
| US20050222534A1 (en) * | 2004-03-30 | 2005-10-06 | Takefumi Uesugi | System and method for supplying predetermined gas at two different pressure values | 
| US8840580B2 (en) * | 2004-03-30 | 2014-09-23 | Olympus Corporation | System and method for supplying predetermined gas at two different pressure values | 
| US20100033120A1 (en) * | 2008-08-06 | 2010-02-11 | Fei Wang | Fan speed control system | 
| US8093854B2 (en) * | 2008-08-06 | 2012-01-10 | Nvidia Corporation | Fan speed control system | 
| US20100145548A1 (en) * | 2008-12-04 | 2010-06-10 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Fan driving circuit | 
| US20110175562A1 (en) * | 2010-01-20 | 2011-07-21 | Hong Fu Jin Precision Industry (Shenzhen)Co., Ltd. | Fan circuit | 
| US8248016B2 (en) * | 2010-01-20 | 2012-08-21 | Hong Fu Jin Precision Industry ( Shenzhen) Co., Ltd. | Fan circuit | 
| US20110243713A1 (en) * | 2010-03-30 | 2011-10-06 | Hon Hai Precision Industry Co., Ltd. | Fan control circuit | 
| US8378614B2 (en) * | 2010-03-30 | 2013-02-19 | Hon Hai Precision Industry Co., Ltd. | Fan control circuit | 
Also Published As
| Publication number | Publication date | 
|---|---|
| CN101477391A (en) | 2009-07-08 | 
| CN101477391B (en) | 2011-11-30 | 
| US20090175602A1 (en) | 2009-07-09 | 
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Legal Events
| Date | Code | Title | Description | 
|---|---|---|---|
| AS | Assignment | 
             Owner name: HONG FU JIN PRECISION INDUSTRY (SHENZHEN) CO., LTD Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:QIAN, CHENG;WANG, NING;HUANG, YONG-ZHAO;AND OTHERS;REEL/FRAME:020551/0068 Effective date: 20080219 Owner name: HON HAI PRECISION INDUSTRY CO., LTD., TAIWAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:QIAN, CHENG;WANG, NING;HUANG, YONG-ZHAO;AND OTHERS;REEL/FRAME:020551/0068 Effective date: 20080219 Owner name: HON HAI PRECISION INDUSTRY CO., LTD.,TAIWAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:QIAN, CHENG;WANG, NING;HUANG, YONG-ZHAO;AND OTHERS;REEL/FRAME:020551/0068 Effective date: 20080219  | 
        |
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| STCH | Information on status: patent discontinuation | 
             Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362  | 
        |
| FP | Lapsed due to failure to pay maintenance fee | 
             Effective date: 20140420  |